Transact SQL :: Count Only Latest Entry

I have a table with below structure, with a sample entry for 1 country:

ID Date              Event CountryCode TxnID
1   22/05/2015   ABC   123   111
2   23/05/2015   XYZ   123   111
3   20/05/2015   XYZ   123   222
4   21/05/2015   ABC   123   222

So, I need to get a count like:

FOR COUNTRYCODE=123
ABC count= 1 
XYZ count= 1

Which means, I want to count for each transaction, the latest entry based on date. And there can be many countries like this. And I need to count both entries for ABC & XYZ.Normal count will give me duplicate entries.